Means for drying buildings



Sept. 10, 1929. KNAPEN mmns FOR DRYING BUILDINGS Filed July 27, 1925 Patented Sept. 10, 1929.

barren STATES PATENT o FF'IcE.

ACI-IILLE KNAPEN, OF BRUSSELS, BELGEUM, A SSIGNOR TO COMPAGNIE GENERALE' D ASSECHEMENT 82; D AERATION, SOCIETE ANONYME, F PARIS, FRANCE.

MEANS FOR DRYING BUILDINGS.

This invention relates to a method of drying buildings by means of single branched evaporation channels or siphons disposed in the thickness of the Walls. In methodsof this type, employed up to the present,use has generally been made of inclined channels, closed at their upper end Within the Wall and the drying effect was obtained by the circulation of air inside the channel, the air entering into the latter being successively charged with moisture and then flowing out, on account of its increased density, along the lower. side of the channels, to escape outside the Wall, taking with it the moisture With which it has become saturated.

Experience has shown'thatthe results obtained by these methods vary a great deal, the action of the dryinglsiphon being rapid in some cases, in others particularly! slow and sometimes even negative, that is to'say bring ing back moisture into the Wall.

The inventorhas sought to find the cause of these unsatisfactory and varying results and has observed from numerous experiments that, in the event of insufficient dryin'gfthe channel or siphon formed in the thicknessol the Wall generally only exerted its action over a part of its length the upper part of the channel forming a cushion of inert air,'that is to say Whichtakes nopart in the circulation. It is possible tov prove,by exp'erin1ent,that these disadvantages are due inmost cases to a bad slope of the evaporation channels. In fact if account is taken of the'fact'that' the layers of atmospheric air Which have access to the drying channel are horizontal layers, it is easy to understand that ii a layer o'l'air under consideration, entering in the form of a sheet into the channel, under the upper edge 40 of the outer orifice of the latter, cannot reach the inner end of the channel'it can only give rise in the latter to a reduced circulation, the Whole volume of air confined inthe upper end of the channel being unable to take part in the Q5 circulation. j I

According to the invention, the drying channels or siphons formed in the thickness ofthe Walls, in order to overcome this disadvantage, are givenan inclination such that a horizontal sheet of air entering into the chan- Application filed July 27, 1925, Serial No. 46,263, and in Belgium: August 2,1924.

nel tangentially to the upper'boun-dingline or the outlet orifice mayescape With a predetermined thickness equal to that Which it possesses when it enters through the opposite end of the channel if the latter is not closed.

Under these conditions the sheet of air considered may exert its drying action over the Whole length of the channel and become charged gradually with moisture the objectionable influence of'the inn er cushion of air being ciiectively overcome. The observing of this condition gives the furtherresult that practically the inclination oi the drying channel or siphon must be inan inverse ratio to the length of the latter inthe thickness of the Wall, the thermal diflerences between the air inside the Wall and the air'in'contactwvitl'i its sides beingasmuch'greater as the Wall is thiclrer and the materials denser... i

In the practicalembodiment of the inven tion,'this inclination varies, in addition, ac} cording to'the position occupied by the drying channel'in the Wall, that isto say in such a Way as to take into account the thermal and hygrometric variations of the layers ofair circulating in the channel. In practice, this inclination varies according as the drying channel is placed at the lower part or at the upper part of a Wall or again insideor outside a room in such a Way that the moving sheet of air, tangential to the end orifices of the drying channel'o'r siphon possesses thicknesses varying to a certain extent'a'ccording to the conditions to be obtained'and' the level or the height at Which it must Work.

The effect ofthe drying channel orsiphon is considerably increased 'When these parts are given a particular cross sectional outline giving rise to one ormore'hygroscopic centres formed by masses suitably disposed for accumulating moisture and in such away as to assist the evaporating action underthe conditions stated above.

The accompanying drawings illustrate by Way of example forms of construction of the invention. 1

Figure 1 showsdiagrammatically, inper spective, a channel having two different in clinations in order to establish b'ycomparison the conditions the inclinationiof'the channel v must fulfil in order to obtain the result sought by the invention.

Figure 2 shows the drying channels arranged in a wall, these channels being placed under the desired conditions to obtain the working of the method.

Figures 3 and l are cross sections of embodiments in which the evaporation channels are formed so as to have masses forming hygroscopic centres which assist, by attracting the surrounding moisture in the zone of their radius of action, the saturation of the sheet of air circulating in the evaporation channel.-

WVith reference toFigure 1 and assuming that a is a channel open at both ends and arranged at a predetermined slope,- it is easily to seethat a horizontal sheet of air 6 of suitable thickness entering this channel tangentially'to the upper bounding line o of the air inlet aperture (Z will meet the lower bounding line 6 of the channel at a point f situated at a considerable distance from the outlet aperture 9. It is obvious that under these conditions the layer of air 7, assuming that a it can become saturated with moisture during its travel through the channel (4 cannot exert any action upon the layers of air contained in the upper part. it of thechannel, since this air, cooled by the evaporation from the surface of contact will flow directly along the lower generating line as its density increases.

The same would not hold if the channel a was inclined as shown at a in such a manner that the layer of air Z), tangential to the upper h part of the inlet orifice d, was also tangential to the inner end 2' of the outlet aperture 9.

Under these conditions the action of the sheet of air will be felt over the whole length of the channel and as a consequence its drying action will be stronger than in the case ofa steeper inclination similar to the one shown for the channel a in Figure 1.

.Figure 2 shows the embodiment of this principle in the case of awall As shown in v this figure, according to the invention the drying channels or siphons is are given an inclination such vthat the condition mentioned with reference to the channel a in Figure 1 is satisfiedi moreover, as shown in F igure 2, in order to take into account the thermal and hygrometric diflerences which may exist, at different points in the height of the wall 70, the inclination of the drying. channels may vary according to their position upon q the height of the wall in such a manner that for a channel it, placed at the upper part of the wall, the thickness of the layer of air Z) is less, for example, than the corresponding thickness of air in a channel placed at the lower part of the wall. It is the thickness of thislayer of air which, according to the thermal and hygrometric conditions and the level of the part in question will determine the, rapidity and efficiency of operation of the dryingchannel or siphon.

Figure 2 shows in dotted lines at 71: the alteration in inclination of such a channel, in the case of a wall of greater thickness, in order to satisfy the condition stated.

Naturally the method of constructing the evaporating channels mentioned above requires that these channels be formed in a homogeneous element of constant porosity, preferably formed separately and then placed in the building to be dried in which channels or cavities such as the hole is shown in Figure 3 are previously prepared. In this case the element which forms the evaporating channel mayoconsist for example of a brick specially constructed and subsequently placed in the thickness of the wall.

Figure 3 shows a brick of this type of triangular form. This brick s which is provided with a circular channel t is placed in a circular cavity 71: formed in the wall. It may be built into this cavity by means of cement or mortar of porosity predetermined according to the case.

lVhenuse is made of evaporation channels thus constructed, it is advantageous to make the member comprising the evaporating channel of special form, for example of polygonal form of the type shown in Figure a for the formation of a channel is.

Figure 4 shows a construction of this type in which the member or brick 3 forms hygroscopic centres t which are distributed at the most suitable points to assist condensation and the, accumulation of moisture in the brick. The distributions of these centres t as shown in Figure a has the advantage over the distribution obtained by adopting the triangular form shown in Figure 3 that the mass forming the hygroscopic centre of greatest accumulationof moisture is at the upper part of the member forming the evaporating channel while two other masses form centres of smaller hygroscopic attraction arranged symmetrically are carried a little below the level of the horizontal diameter of the channel. In the example shown in Fig. 4, the upper surface of the channel 27 is pro vided with angular teeth 20; these angular grooves are provided for the purpose of increasing the evaporating and consequently cooling surface and of consequently accele rating the removal of moisture which accumulates in the'saturated brick, due to the attraction it exerts, on account of its special shape, upon the moisture contained in the surrounding parts of the wall is constantly drawn into the radius of. action of the member forming the siphon.

What I claim is 1. In a building wall, means for drying said open end and of such inclination that the lowermost point of its inner end is substantially below the uppermost point of its outer end whereby a horizontal sheet of air entering the conduit may reach the innermost end of the conduit and establish a circulation throughout the entire length of the conduit.

2. In a building wall means for drying g said wall comprising a conduit therein ex- 10 tending transversely from one surface of the said wall to a point Within the other surface of the said wall, said conduit being inclined with its inner closed end relatively higher than its outer open end and of such inclination that the lowermost point of its inner end is substantially below the uppermost point of its outer end, the inclination being inversely proportional with respect to the length of the conduit whereby a horizontal sheet of air entering the conduit may reach the innermost end of the conduit and establish a circulation throughout the entire length of the conduit.

8. In a building wall, means for drying said wall comprising a plurality of conduits arranged at varying heights therein and extending transversely from one surface of said wall to a point within the other surface of said wall said conduits being inclined with their inner closed ends relatively higher than their outer open ends respectively and of such inclinations that the lowermost point of their inner ends are substantially below the uppermost point of their outer ends whereby a horizontal sheet of air entering the conduits may reach the innermost ends thereof and establish a circulation throughout the entire length of the conduit, the inclination of said conduits increasing pro- 0 portionately to their heights in said wall whereby a thicker sheet of air may enter the lower conduits relatively to the higher conduits.

In testimony whereof I have affixed my 5 signature.

AOHILLE KNAPEN 

